Biology subjects

Oda, M.

Publications and source records attributed to Oda, M..

5 recordsLinked to original sources

bioRxiv2026

Calibrated ADAMTS13 inhibition prevents cardiovascular shear coagulopathy

Mechanical circulatory support essential for managing severe heart failure frequently triggers bleeding complications, driven by shear stress-induced over-proteolysis of von Willebrand factor (VWF) by ADAMTS13. Inhibiting ADAMTS13 presents a rationale to treat this condition, known as acquired von Willebrand syndrome (AVWS). However, conventional therapeutic strategies remain limited due to the risk of triggering thrombotic thrombocytopenic purpura. Here we show that HA10, a humanized anti-ADAMTS13 antibody, preserves a residual level of ADAMTS13 activity above the thrombosis-associated threshold. Multimodal structural and biophysical analyses--including NMR, SAXS, and SANS--revealed that HA10 bound to the disintegrin-like domain of ADAMTS13, dynamically competing with VWF while leaving 10- 20% residual enzymatic activity. The therapeutic efficacy and safety of HA10 were verified in non-human primate models of AVWS. Our findings establish a novel paradigm of enzymatic calibration rather than complete blockade, offering a mechanistically targeted and safe therapeutic approach for cardiovascular bleeding.

biochemistry↗

bioRxiv2024

Structural and functional dissection of the Pacinian corpuscle reveals an active role of the inner core in touch detection

Pacinian corpuscles are rapidly adapting mechanoreceptor end-organs that detect transient touch and high-frequency vibration. In the prevailing model, these properties are determined by the outer core, which acts as a mechanical filter limiting static and low-frequency stimuli from reaching the afferent terminal--the sole site of touch detection in corpuscles. Here, we determine the detailed 3D architecture of corpuscular components and reveal their contribution to touch detection. We show that the outer core is dispensable for rapid adaptation and frequency tuning. Instead, these properties arise from the inner core, composed of gap junction-coupled lamellar Schwann cells (LSCs) surrounding the afferent terminal. By acting as additional touch sensing structures, LSCs potentiate mechanosensitivity of the terminal, which detects touch via fast-inactivating ion channels. We propose a model in which Pacinian corpuscle function is mediated by an interplay between mechanosensitive LSCs and the afferent terminal in the inner core. HighlightsO_LIeFIB-SEM reveals detailed 3D architecture of the entire Pacinian (Herbst) corpuscle C_LIO_LIInner, not outer core mediates rapid adaptation and frequency tuning C_LIO_LIAfferent terminal detects touch via fast-inactivating ion channels C_LIO_LIMechanosensitive lamellar Schwann cells tune afferent terminal sensitivity to touch C_LI

neuroscience↗

bioRxiv2023

Improvement of thermostability and activity of PET-degrading enzyme Cut190 towards a detailed understanding and application of the enzymatic reaction mechanism

Enzymes capable of hydrolyzing polyethylene terephthalate (PET) and other plastics are attractive catalysts for application to the recycling of plastic waste due to their generally low environmental impact. Cut190 is a cutinase from a thermophilic actinomycete and shows PET-degrading activity and high thermal stability. We developed a series of Cut190 mutants exhibiting further improvements in thermal stability and activity, and showed that the unique stabilization and activation mechanism was dependent on Ca2+ ions. Two of these mutants, Cut190** and Cut190*SS, differed from the previous mutant Cut190* by deletion of the three C-terminal residues and introduction of five substitutions, including two cysteines forming a disulfide-bond, respectively. These mutants exhibit higher thermal stability and activity, which are often mutually exclusive characteristics. Crystallographic studies of these mutants and their inactivated derivatives demonstrated that they could have a novel ejecting form that would be responsible for releasing products. We also determined the crystal structures of ligand-bound complexes, which revealed the molecular mechanisms of the aromatic-ring recognition and the tetrahedral intermediate during the substrate cleaving, although the ligands had no aromatic ring but a cyclic group. This structural information provides insights into the mechanism of the Ca2+ -dependent PET-cleaving activity of Cut190 and provides a useful basis for further mutant design and computational studies.

biochemistry↗

bioRxiv2019

Perturbation of the titin/MURF1 signaling complex is associated with hypertrophic cardiomyopathy in a fish model and in human patients.

Hypertrophic cardiomyopathy (HCM) is a hereditary disease characterized by cardiac hypertrophy with diastolic dysfunction. Gene mutations causing HCM have been found in about half of the patients, while the genetic etiology and pathogenesis remain unknown for many cases of HCM. To identify novel mechanisms underlying HCM pathogenesis, we generated a cardiovascular-mutant medaka fish non-spring heart (nsh), which showed diastolic dysfunction and hypertrophic myocardium. The nsh homozygotes had fewer myofibrils, disrupted sarcomeres and expressed pathologically stiffer titin isoforms. In addition, the nsh heterozygotes showed M-line disassembly that is similar to the pathological changes found in HCM. Positional cloning revealed a missense mutation in an immunoglobulin (Ig) domain located in the M-line-A-band transition zone of titin. Screening of mutations in 96 unrelated patients with familial HCM, who had no previously implicated mutations in known sarcomeric gene candidates, identified two mutations in Ig domains close to the M-line region of titin. In vitro studies revealed that the mutations found in both medaka fish and in familial HCM increased binding of titin to muscle-specific ring finger protein 1 (MURF1) and enhanced titin degradation by ubiquitination. These findings implicate an impaired interaction between titin and MURF1 as a novel mechanism underlying the pathogenesis of HCM.

developmental biology↗

bioRxiv2018

An inhibitor-interaction intermediate of HIV-1 protease, revealed by Isothermal Titration Calorimetry and NMR spectroscopy

Some of drug-resistant mutants of HIV-1 protease (PR), such as a clinically-relevant drug- resistant PR mutant (Flap+(I54V)) containing L10I, G48V, I54V and V82A mutations, produce significant changes in the balance between entropy and enthalpy of the drug-PR interactions, compared to the wild-type (WT) PR. Here, to gain a comprehensive understanding of the entropy-enthalpy compensation effects, we compared nuclear magnetic resonance (NMR), fluorescence spectroscopy and isothermal titration calorimetry (ITC) data of a WT PR with Flap+(I54V) and related mutants: (1) Flap+(I54V); (2) Flap+(I54A) which evolves from Flap+(I54V) in the continued presence of inhibitor yet does not exhibit entropy-enthalpy compensation; and (3) Flap+(I54), a control mutant that contains only L10I, G48V and V82A mutations. Our data indicate that WT and Flap+(I54A) show enthalpy-driven inhibitor-interaction, while Flap+(I54) and Flap+(I54V) exhibit entropy-driven inhibitor interaction. Interestingly, Flap+(I54A) exhibited significantly slower heat flow in the competitive ITC experiment with a strong binder, darunavir, and a weak binder, acetyl-pepstatin, but did not exhibit such slow heat flow in the direct inhibitor-titration experiments. NMR confirmed replacement of the weak binder by the strong binder in a competitive manner. This difference in the heat flow of the competitive binding experiment compared to the direct experiment can only be explained by assuming an inhibitor-bound intermediate pathway. A similar, but attenuated, tendency for slow heat flow was also detected in the competitive experiment with WT. Overall, our data suggests that an inhibitor-bound intermediate affects the entropy-enthalpy compensation of inhibitor-PR interaction.

biochemistry↗